Impaired Pre-operative Ambulatory Capacity in Patients Undergoing Elective Endovascular Infrarenal Abdominal Aortic Aneurysm Repair is Associated with Increased Peri-operative Death

Objective: While ambulatory capacity is a readily assessable clinical indicator of functional status, its association with outcomes after endovascular aneurysm repair (EVAR) remains underexplored. This study aimed to investigate the association between pre-operative ambulatory status and outcomes following elective EVAR.

Methods: A retrospective review of the multi-institutional Vascular Quality Initiative database was conducted for all patients who underwent elective infrarenal EVAR from 2009 - 2022. Patients were categorised into independent ambulation and impaired ambulation groups. A propensity score matched analysis was performed to produce two well matched cohorts in a 1:1 ratio without replacement. The primary outcome was 30 day death. Secondary outcomes included one year survival and in hospital major complications.

Results: Among 11 474 patients, 10 539 (91.8%) were independently ambulatory pre-operatively. Propensity score matching resulted in 885 matched pairs. The impaired ambulation group, although older (mean 77.6 vs. 76.3 years; p = .001), showed comparable baseline characteristics. Post-operatively, the impaired ambulation group had higher cumulative in hospital complications and death as well as 30 day death. Even after adjustment for age, impaired pre-operative ambulation was associated with increased in hospital and 30 day death (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.26 - 3.95; p = .006). Multivariable analysis demonstrated increasing cumulative risk of 30 day death in the setting of impaired pre-operative ambulatory status with age > 75 years requiring post-operative red blood cell transfusion > 2 units (HR 5.75, 95% CI 2.09 - 15.88; p < .001). Beyond 30 days, impaired pre-operative ambulation was not associated with increased one year death (HR 1.09, 95% CI 0.81 - 1.48; p = .570).

Conclusion: Among patients who underwent elective infrarenal EVAR in this matched analysis, impaired pre-operative ambulatory capacity was associated with an increased risk of in hospital and 30 day death, further compounded by advanced age and post-operative transfusion. As such, a threshold higher than the traditional size criteria should be considered in shared decision making when determining options for the management of abdominal aortic aneurysm in this high risk cohort.